Pérotin (fl. c. 1200) was a French composer associated with the Notre Dame school of polyphony in Paris, the leading center of the ars antiqua style. He is credited with expanding earlier two‑voice organum into the monumental three‑ and four‑voice textures that shaped the development of Western polyphony. His works, including Viderunt omnes and Sederunt principes, are known through the writings of Anonymous IV, who praised him as a master of rhythmic and architectural innovation.
